In this convention, as for the shin part(11), calf part(15), instep part(12), and sole part(15), with inner threads made with yarn single covered with polyurethane long staple or long copolymer fiber, and separate nylon 70D/24F/1 high speed textured yarn wound on highly elastic lycra soft yarn by double covering method at optimum conditions, maintaining the expansibility of the lycra soft yarn which is the wadding thread, providing and utilizing the strong force of restitution which is the characteristics of the lycra soft yarn, with the covering technology of lycra soft yarn double covered with nylon 70D/24F/1 high speed textured yarn, providing the same kind but different characteristics,
and by using the said highly elastic yarn as the elastic yarn gradually from the sole(15) up to the shin part(11) with the application of multi-stage compression knitting technology in accordance with the leg shape, with elastic yarn rib fabrication in 1:1, 2:2, or 3:1 for gradual decompression from sole(15) to the shin(11), giving the jar-like shape at the shin part(11).
Consequently, the socks produced by the art of this invention have the shape fit for the leg as well as the characteristics of an artificial functional skin giving soft but strong tightness promoting the blood flow in foot by elastic compression, preventing and curing the varix and edema, a knitting design technology based on human engineering.
By adding the heat treatment technology such as piece dyeing, the high elasticity of the product is further enhanced.
In addition, by winding separate nylon 70D/24F/1 high speed textured yarn by the double covering method at optimum conditions on lycra soft yarn, general elastic yarn feeding devices can be used without separate slip prevention devices which are required exclusively for polyurethane yarn, enabling mass production at lower production cost. And by using the said highly elastic yarn in order to make use of the restitution force which is the characteristics of the lycra soft yarn, while maintaining(restraining) appropriate expansibility by double covering technology, in order to solve the problems in using the double covering yarn of latex based material which is the general material of socks, providing a higher grade physical characteristics(soft and strong elasticity).
As for the parts where the high elastic yarn is used, it is not a specific part but all over the sock that makes use of the said highly elastic yarn. The optimum tightness in accordance with the body shape is obtained by the speed control of the yarn at the sock knitting machine, implementing multi-stage compression knitting technology all over the sock except the heel and toe, propelling the blood stream in foot circulate back to the heart. Therefore, for the knee-high socks, medical-care-type socks can be produced preventing and curing the varix and edema.
This invention is characterized by utilizing the strong force of restitution and lower expansibility yarn with the implementation of multi-stage compression technology for producing socks.